In a sauté pan or in a baking dish cook the bratwurst, using a little oil; remove when done.
In the same pan or baking dish, cook the catfish.
Thinly slice the bratwurst and place on top of the fish.
Serve with your favorite mustard and coleslaw.
Notes
Coleslaw is a very personal thing, the kind you like is the only kind there is. I personally like very thinly shredded green cabbage, lightly salted with a little mayonnaise tossed in. Most people like a little sugar or honey in the dressing.